Process of manufacture of tungsten dioxid.



- erin, or the like.

' specification.

UNITED STATES PATENT OFFHJE.

ANTON LEDERER, OF VIENNA, AUSTRIA-HUNGARY, ASSIG'NOR TO WESTINGHOUSE LAM]? COMPANY, A CORPORATION 011' 'PENNS'YLVANIA.

PROCESS OF 'MAIN'UFQiCTUBTd OF TUNGSTEN DIOXID.

No Drawing.

Specification of Letters Patent. Patented Feb. 14 1911,

' Application fil ed September 6, 1907. Serial No. 391,662.

subject of the Emperor of Austriallungary,

and a resident of Vienna, Austria-Hungary, have im ented a new and useful Improvement in Processes of Manufacture of Tungsten Dioxid, of which the following is a The present invention relates to a ess of obtaining tungsten dioxid.

The process consists in mixing with tung sten trioxid an aliphatic liydroxyl com pound, such as glycerin, ethylene glycol, or the like, preferably in the proportions of about ten parts by Weight of tungstic acidto about one-half a part by Weight of glycerin, ethylene glycol, or' other equivalent substance. The mass should be intimately mixed and this can be eifected by adding to the glycerin, ethylene glycol or the like, water or some other suitable fluid which will aid in producing a uniform distribution of the reducing medium throughoutthe tungstic acid, The drying process may be car'- ried on at the temperature at which the diluting material evaporates, but should-be below the decomposin temperature of glyc- Tl e glycerin. or other equivalent substance may be mixed with the solvent in undiluted form under constant stirring. The mass is then slowly dried, the result being that the diluent alone evaporates. The mixture thus obtainedis heated to red heat, preferably in a non-oxidizing atmosphere, for a consider able time (about, 2- 5 hours) according to the amount of material used and the temperature. When this process is properly carried out the brown'dioxid of tungsten ready for use isobtained after cooling takes lace.

Instead of the tricxid of tungsten or the tungstic acid, it is possible to treat intermediate oxi'ds of tungsten in a similar mannor and obtain the same results.

In carry ng outthe described process ,it 1S of great importance that care should be taken that the materials used are perfectly free from. alkaline substances.

I claim as my invention V 1. Theymethod of manufacturing tong sten d tox-id from the higher oxids of twig-- sten, which consists in intimately mixing procv.phatic hydroxyl compound, and then subjecting the mixture tora high temperature the same ,with a proper proportion of aliin a non-oxidizing atmosphere.

2. The method of manufacturing 'tung-' sten. dioxid irom higher oxygen compounds of tungsten, which consists in intimately mixing with the same a proper proportion of aliphatic hydroxyl compound such as described, adding-to the mixture a yolatile liquid lighter than the reducing medium,

mixing thoroughly, drying the completed mixture so as to evaporate the volatile medium, and subjecting the resulting product to a high temperature in a non-oxidizing atmosphere. r v

3. The method of manufacturing. tungsten dioxid from a higher oxygencompound of tungsten, which consists in taking the oxygen compound anda reducing medium such as'des'cribed, adding a diluting liquid,

' intimately mixing the same and evaporating the diluting medium, and subjecting the resulting product to a high temperature.

4. The method of manufacturing tungsten dioxidfrom the higher oxids of tungsten, which consists in intimately mixing the. latter with a proper proportion of glyccrin and then subjecting the mixture to a high temperature.

In testimony whereof I have hereunto subsrcribed my name this 10th day of August 190 I I ANTON LEDERER. Witnesses:

, Smennueo NnUTnir,-

Rom. "W. Hn ueanrnnn. 

